For providing torque to a secondary drive shaft of an all-wheel drive vehicle, U.S. Pat. No. 7,150,694 is an example of using a clutch in a power transfer unit (PTU), which adds to the mass and size of the PTU. U.S. Pat. No. 7,150,694 and U.S. Pat. No. 7,309,301 are examples of using a transfer (typically wet) clutch in a differential to control torque to a secondary drive shaft. Pressurized fluid must be continuously supplied to keep the clutches in a closed mode, adding to the power usage associated with usage of the clutches. U.S. Pat. No. 6,520,885 is an example of using a roller or dog clutch to control torque to a secondary drive shaft. However, a vehicle must be at a stand still to use of such clutches.